Unable to update Kit back fsh files

[Enjay2008]

Everytime I try to upgrade the images in the kit back fsh files, the new image overwrites the first old image successfully, but when I select the second image and import the new graphic it over writes the first imported image and not the second one, bringing in the 3rd​ image it does the same over writes the first and not the third. This only happens with kit back fsh files all the others I can change quite happily. This happens with the aready modified fsh files as well as the originals from the data.gob file.